Myths vs facts: Fertility Check and longevity

Myths vs. Facts: Fertility Check and Longevity Many direct-to-consumer DNA tests claim to assess fertility or longevity. The scientific reality is more nuanced. Fertility checks often include SNPs like MTHFR (rs1801133) or FTO, but these have small effect sizes and are not diagnostic. Female fertility depends on age, hormones, and lifestyle; male fertility on sperm quality. A single SNP cannot predict infertility. Longevity tests frequently highlight FOXO3 (rs2802292) or other variants, but GWAS associations are weak and population-specific. No validated polygenic score for longevity exists for individual use. The evidence is mixed: some SNPs have mechanistic plausibility, but clinical utility is lacking. Marketing often exaggerates these findings. Consumers should be aware that lifestyle factors (diet, exercise, sleep, stress) have far greater impact than any single gene. Safety note: Do not start supplements (e.g., selenium, NAC) based on these tests without medical advice. Evidence grade: mixed/unclear. Sources: GWAS catalog, expert reviews.